With the development of communication technologies, a lot of new technologies emerge, where a very typical one is CoMP (Coordinated Multi-point Transmission, coordinated multi-point transmission). Among various types of CoMP, MU-MIMO (Multi User Multi Input Multi Output, multi user multi input multi output) has the most significant gain.
A basic goal of the MU-MIMO is to increase an average data rate of users, and perform precoding for spatially-separated antennas “collaboratively” by sharing a data stream, so as to implement optimized communication with multiple user equipments. In the MU-MIMO, a transmitter performs different precoding on data of different users, and then sends the precoded data by using the spatially-separated antennas. Receivers of different users performs decoding on the received data to obtain their respective data. The MU-MIMO eliminates mutual interference between different users through precoding, and achieves a purpose of sending data to multiple users at the same time.
A user needs to know a code book used by a network side or a precoding matrix formed by using the code book, so that decoding and obtaining the data can be performed. Therefore, the network side needs to send a precoding matrix index or a pilot sequence to each user. Because different data streams of different users adopt different code books, the network side needs to send the precoding matrix index or the pilot sequence to the users.
In the prior art, a large number of precoding matrix indexes are sent, which occupies a lot of resources.